In production of glass fibers, significant amounts of waste glass-based fibrous materials are formed in production steps performed. These waste glass-based fibrous materials mainly consist of long fibers, usually having lengths within a range of 5 to 10 m.
US 2007/0042890 describes a process in which fibers are coarsely cut at first and then ground in a ball mill.
U.S. Pat. No. 6,032,883 describes a process for processing glass fibers in which glass fibers are mixed with small amounts of glass powder, broken glass or water.